IL-6R was expressed in all patients with AML and AMLL, whereas only half of ALL patients expressed low levels of IL-6R as compared with those with AML and AMLL.
However, gp130 was ubiquitously expressed in all the leukemia patients, and there was no significant difference in gp130 expression among AML, ALL, and AMLL.
Although the specificity of CD117 in this study is not as high as CD14 and CD64, markers concomitantly used in this this study and in the WHO classification, based on the results of other researches (i.e. the specificity of CD117 for AML was 100% in one study) and due to the fact that its specificity for AML in this study is relatively high, we recommend the use CD117 in assigning a myeloid lineage in MPAL.
Specific subsets of MPAL are defined by chromosomal anomalies such as the t(9;22) Philadelphia chromosome BCR-ABL1 or involvement of the MLL gene on chromosome 11q23.
From a clinical practice standpoint, this case illustrates the importance of detection of MLL rearrangement due to its prognostic implication and the effectiveness of flow cytometry immunophenotyping in diagnosing MPAL and monitoring minimal residual disease.
However, gp130 was ubiquitously expressed in all the leukemia patients, and there was no significant difference in gp130 expression among AML, ALL, and AMLL.
Although rare, CALM/AF10 is a chromosomal rearrangement found in immature T-cell acute lymphoblastic leukemia (T-ALL), acute myeloid leukemia, and mixed phenotype acute leukemia of T/myeloid lineages with poor prognosis.
Impairment in function of GST and MTHFR enzymes found in our patient may have contributed to the development of secondary mixed phenotype acute leukemia, although precise mechanism remains elusive.
However, gp130 was ubiquitously expressed in all the leukemia patients, and there was no significant difference in gp130 expression among AML, ALL, and AMLL.
Taken together, our data suggest that BTG1 deletions might play a role in leukemogenesis of BCP-ALL as well as of BCR-ABL1-positive MPAL and CML-BC (B-lineage).